Glioma cases were clustered into four groups: IDH-mut/TERTp-mut (positive for both IDH and TERTp mutations), IDH-mut/TERTp-wt (positive IDH mutation, but negative for TERTp mutations), IDH-wt/TERTp-mut (positive TERTp mutations, but negative for IDH mutations), and IDH-wt/TERTp-wt (no IDH or TERTp mutations). This evidence concerns the gene IDH1 and glioma.